Degradation of Plant Lignin with The Supercritical Ethanol and Ru/C Catalyst Combination for Lignin-oil

초임계 에탄올과 루테늄 촉매에 의한 초본 리그닌의 오일화 반응

Park, Jeesu;Kim, Jae-Young;Choi, Joon Weon

  • Received : 2014.10.28
  • Accepted : 2014.12.10
  • Published : 2015.05.25


Asian lignin was efficiently depolymerized with supercritical ethanol and Ru/C catalyst at various reaction temperature (250, 300, and $350^{\circ}C$). Lignin-oil was subjected to several physicochemical analyses such as GC/MS, GPC, and elemental analysis. With increasing reaction temperature, the yield of lignin-oil decreased from 89.5 wt% to 32.1 wt%. The average molecular weight (Mw) and polydispersity index (Mw/Mn) of lignin-oil obtained from $350^{\circ}C$ (547Da, 1.49) dramatically decreased compare to those of original asian lignin (3698Da, 2.68). This is a clear evidence of lignin depolymerization. GC/MS analysis revealed that the yield of monomeric phenols involving guaiacol, 4-ethyl-phenol, 4-methylguaiacol, syringol, and 4-methysyringol increased with increasing reaction temperature, and these were mostly produced with applying hydrogen gas and Ru/C catalyst (76.1 mg/g of lignin). Meanwhile, the carbon content of lignin-oil increased whereas the oxygen content decreased with increasing reaction temperature, suggesting that hydrodeoxygenation was significantly enhanced at higher temperature.


lignin;depolymerization;supercritical ethanol;Ru/C;phenols


  1. Amen-Chen, C., Pakdel, H., Roy, C. 2001. Production of monomeric phenols by thermochemical conversion of biomass: a review. Bioresource Techonology 79: 277-299.
  2. Brands, D., Poels, E., Dimian, A., Bliek, A. 2002. Solvent-based fatty alcohol synthesis using supercritical butane. Thermodynamic analysis. American Oil Chemists' Society 79: 75-83.
  3. Brunow, G., Lundquist, K. 2010. Functional groups and bonding patterns in lignin (including the lignin-carbohydrate complexes). CRC Press, Boca Raton, USA.
  4. Dence, C.W. 1992. The determination of lignin. Methods in lignin chemistry. Springer Berlin Heidelberg 33-61.
  5. Fan, M., Jiang, P., Bi, P., Deng, S., Yan, L., Zhai, Q., Wang, T., Li, Q. 2013. Directional synthesis of ethylbenzene through catalytic transformation of lignin. Bioresource Technology 143: 59-67.
  6. Fang, Z., Sato, T., Smith Jr, R.L., Inomata, H., Arai, K., Kozinski, J.A. 2008. Reaction chemistry and phase behavior of lignin in high-temperature and supercritical water. Bioresource Technology 99: 3424-3430.
  7. Gosselink, R.J.A., Teunissen, W., van Dam, J.E.G., de Jong, E., Gellerstedt, G., Scott, E.L., Sanders, J.P.M. 2012. Lignin depolymerisation in supercritical carbon dioxide/acetone/water fluid for the production of aromatic chemicals. Bioresource Technology 106: 173-177.
  8. Gutierrez, A., Kaila, R., Honkela, M., Slioor, R., Krause, A. 2009. Hydrodeoxygenation of guaiacol on noble metal catalysts. Catalysis Today 147: 239-246.
  9. Holmelid, B., Kleinert, M., Barth, T. 2012. Reactivity and reaction pathways in thermochemical treatment of selected lignin-like model compounds under hydrogen rich conditions. Journal of Analytical and Applied Pyrolysis 98(0): 37-44.
  10. Kim, S., Dale, B.E. 2004. Global potential bioethanol production from wasted crops and crop residues. Biomass Bioenergy 26: 361-375.
  11. Kim, J.-Y., Oh, S., Hwang, H., Cho, T.-S., Choi, I.-G., Choi, J.W. 2013. Effects of various reaction parameters on solvolytical depolymerization of lignin in sub-and supercritical ethanol. Chemosphere 93: 1755-1764.
  12. Kim, J.-Y., Park, J., Kim, J.K., Song, I.K., Choi, J.W. 2014. Catalytic depolymerization of lignin macromolecule to alkylated phenols over various metal catalysts in supercritical t-butanol. Journal of Analytical and Applied Pyrolysis, Accepted.
  13. Lapierre, C. 2010. Determining lignin structure by chemical degradations. Lignin and Lignins: Advanced in chemistry. Heitner C., Dimmel D., Schmidt J.A. 11. Boca Raton, FL: CRC Press, Taylor & Francis Group.
  14. Li, H., Yuan, X., Zeng, G., Tong, J., Yan, Y., Cao, H. 2009. Liquefaction of rice straw in sub-and supercritical 1, 4-dioxane-water mixture. Fuel Processing Technology 90: 657-663.
  15. Long, J., Zhang, Q., Wang, T., Zhang, X., Xu, Y., Ma, L. 2014. An efficient and economical process for lignin depolymerization in biomass-derived solvent tetrahydrofuran. Bioresource Technology 154: 10-17.
  16. Lu F., Ralph J. 1997. Derivatization followed by reductive cleavage (DFRC method), a new method for lignin analysis: protocol for analysis of DFRC monomers. Agricultural and Food Chemistry 45(7): 2590-2592.
  17. Pandey, M.P., Kim, C.S. 2011. Lignin Depolymerization and Conversion: A Review of Thermochemical Methods. Chemical Engineering & Technology 34(1): 29-41.
  18. Regauskas, A.J., Williams, C.K., Davison, B.H., Britovsek, G., Cairney, J., Eckert, C.A., Rederick Jr., W.J., Hallett, J.P., Leak, D.J., Liotta, C.L. 2006. The path forward for biofuels and biomaterials. Science 311: 484-489.
  19. Tan, H.T., Lee, K.T. 2012. Understanding the impact of ionic liquid pretreatment on biomass and enzymatic hydrolysis. Chemical Engineering 183: 448-458.
  20. Vazquez, G., Antorrena, G., Gonzalez, J., Freire, S. 1997. The influencing of pulping conditions on the structure of acetosolv eucalyptus lignins. Wood Chemistry and Technology 17(1 and 2): 147-162.
  21. Yoshikawa, T., Yagi, T., Shinohara, S., Fukunaga, T., Nakasaka, Y., Tago, T., Masuda, T. 2013. Production of phenols from lignin via depolymerization and catalytic cracking. Fuel Processing Technology 108: 69-75.
  22. Wild, De., P.J., Huijgen, W.J.J., Heeres, H.J. 2012. Pyrolysis of wheat straw-derived organosolve lignin. Journal of analytical and applied pyrolysis 93: 95-103.


Supported by : 산림청, 한국연구재단